Anaesthetics

Front 1

tetrodotoxin (TTX)

Back 1

Class: local anaesthetic
Action: blocks Na+ ch. at sites near extracellular surface; blocks conduction w/o change in RMP.

Front 2

procaine

Back 2

Class: ester-type local anaesthetic
Short duration of action, rel. potency of 1.

Front 3

chloroprocaine

Back 3

Class: ester-type local anaesthetic
Duration: short
Rel. Potency: 1

Front 4

cocaine

Back 4

Class: ester-type local anaesthetic
Duration: med
Rel. Potency: 2

Front 5

tetracaine

Back 5

Class: ester-type local anaesthetic
Duration: long
Rel. potency: 16

Front 6

mepivacaine

Back 6

Class: amide-type local anaesthetic
Duration: medium
Rel. potency: 2

Front 7

prilocaine

Back 7

Class: amide-type local anaesthetic
Duration: medium
Rel. potency: 3

Notes: metabolite o-toluidine can oxidise Hb to methemboglobin.

Front 8

lidocaine

Back 8

Class: amide-type local anaesthetic
Med. duration of action, rel. potency of 4.

Front 9

bupivacaine

Back 9

Class: amide-type local anaesthetic
Duration: long
Rel. potency: 16
Notes: cannot be given I.V. due to potential for severe cardiotoxicity; not suitable for intravenous block.

Front 10

ropivacaine

Back 10

Class: amide-type local anaesthetic
Duration: long
Rel. potency: 16

Front 11

Nitrous Oxide

Back 11

Class: inhaled GA
Action: inhibits NMDA RR
Toxicity: no sig. short-term toxicity or met. Will expand pockets of trapped gas. Inhibits methionine synthetase; megaloblastic anaemia with extended exposure.
Potency: poor
Analgaesia: good
Notes: use 70% N2O in conjuction with other GAs.

Front 12

Halothane

Back 12

Class: Inhaled GA
Analgesia: slight
Sk Mm relax.: slight
Pungency: low; pt. friendly.
Solubility: int.
Side effects/tox.: myocardial depressant, sensitises myocardium to catecholamines. Dose-dependent ↓BP. F- toxic. ↓renal bloodflow. ↑intracranial pressure, due to sm mm relaxation (vasodilation). Halothane Hepatitis 1/35,000 chance.
Notes: "gold standard".

Front 13

Isoflurane

Back 13

Class: Inhaled GA
Action:
Solubility: less than halothane.
Potency: less than halothane
Analgesia:
Pungency: more than halothane.
Toxicity: less than halothane; less met.
Side effects: ↑'d HR, but mainatains C.O.
Notes: potentiates tubocurarine

Front 14

Enflurane

Back 14

Class: Inhaled GA
Action:
Potency: less than halothane
Analgesia: more sk mm relaxation than halothane.
Pungency: more than halothane.
Toxicity: less than halothane; less met.
Side effects: less bradycarida, less likely to sensitise to catecholamines. Less ↑ in intracranial pressure.
Contra: may exacerbate seizures.
Notes: not commonly used.

Front 15

Methoxyflurane

Back 15

Class: Inhaled GA
Action:
Potency: high; highly soluble, low MAC.
Toxicity: high (due to high solubility), esp. nephrotoxicity.
Analgesia:
Notes: No longer in wide use. Long recovery time.

Front 16

Sevoflurane

Back 16

Class: Inhaled GA
Action:
Potency: lower
Analgesia:
Sm mm: good relaxant; bronchodilation.
Toxicity: more than isoflurane due to higher met.
Pungency: Low
Notes: excellent control, rapid induction/recovery.

Front 17

Desflurane

Back 17

Class: Inhaled GA
Action:
Potency: lower; low solubility, quick induction/recovery.
Pungency: high; use IV induction.
Analgesia:
Toxicity: little met.
Side effect: ↑HR, maintains C.O.
Notes: Suited for ambulatory surgery; quick recovery.

Front 18

thiopental

Back 18

Class: IV GA
Action: Activates GABA-A R, ↑s Cl- conductance, hyperpolarises.
Potency: low; rapid induction, short duration.
Analgesia:
Side effects: Cardiovascular/respiratory depressant. Unpredictable hypersensitivity reactions due to sulfur grp.
Contrain: weakly basic drugs, because thiopental is a poorly soluble weak acid.
Notes:

Front 19

methohexital

Back 19

Class: IV GA
Potency: 3x higher than thiopental.
Duration: 2x shorter

Front 20

Midazolam

Back 20

Class: benzodiazepine used as IV GA
Solubility: higher than diazepam.
Half-life: 3 hours
Analgesia: none, but induces anterograde amnesia
Side effects: less cardio/resp. effects than most barbituates.
Notes: flumazenil reverses.

Front 21

Ketamine

Back 21

Class: IV GA,
Action: inhibits NMDA RR, like N2O.
Effect: dissociative anaesthesia. No generalised relaxation.
Analgesia: good, suitable for burn pts.
Side effects: cardiovascular stimulant, hallucinations, ↑s intracranial/intraocular pressure.

Front 22

Etomidate

Back 22

Class: IV GA
Analgesia: none
Advantages: preserves resp. stability, C.O.
Side effects: myoclonus, adrenal suppresion (thus used only for induction). Painful to inject.

Front 23

Propofol

Back 23

Class: IV GA
Advantages: rapid recovery, anti-emetic properties. Suitable for day-surgery.
Side effect: very resp. depressive; transient apnea, ↓BP, pain on injection, contamination of lipid vehicle.
Contra: cardiac disease.

Front 24

fentanyl

Back 24

Class: narcotic as IV GA
Effect: opioid anaesthesia.
Analgesia: good
Half-life: shorter than other opioids.
Side effects: severe resp. depression, minimal cardiovascular depression, mm rigidity.
Notes: naloxone for reversal.

Front 25

Droperidol

Back 25

Class: IV GA
Effect: neuroleptanaesthesia, anti-emetic, anti-fibrillatory/convulsant.

Front 26

Dexmedetomidine

Back 26

Class: α2-agonist used as IV GA.
Effect: sedative/analgesic properties, conscious sedation.
Half-life: shorter than most α2-agonists, rapid recovery.
Notes: metabolised in liver by esterases, used in veterinary medicine.